Professor Steven Hawking is from the UK and thus would speak with an English accent if he were not impaired by his condition. When Professor Hawking ends the interview, he gets up from the wheelchair and speaks with an American accent. However, this is clearly a joke. See more
Stewie, can you please move? You're blocking the TV.
No! And I'll thank you to quiet down, I'm playing action figures. "Prepare to be bested on the battlefield, Lion-O". "Oh, I don't think so, He-Man... Ow!". "Oh, I'm sorry, did I punch you too hard?". "Yes, I suppose you don't know your own strength; I mean, look at your muscles!". "Oh, stop! You're the one with the sick abs". "God, my mouth is watering just looking at you". Yeah, that's right... you buy your kids ridiculously homoerotic dolls...